fixed logic error in empty-collection-message that caused crash

[stevemadere]

when search results were empty

[iox]

That's very interesting, I though nil.nil? would always return true.

I will merge it, but I would like to learn more, so I don't repeat the same issue in the future. Has this anything to do with the Ruby or Rails version?

Warm regards,
Igancio

[iox]

Hi Steve,

Unfortunately, I have had to revert your pull request. In Codeship, and in my local environment, the search results were failing with undefined methodname' for nil:NilClassinhobo_rapid/taglibs/lists/empty_collection_message.dryml:8`

Any idea what the problem could be?

[stevemadere]

nil.nil? is true

NilClass.nil? is not true.

Notice that the code I changed is calling member_class and checking
if it is nil.

The call to member_class is returning NilClass rather than nil.

That seems reasonable to me, given the name of the method.

On Sat, Nov 7, 2015 at 3:35 AM, Ignacio Huerta notifications@github.com
wrote:

That's very interesting, I though nil.nil? would always return true.

I will merge it, but I would like to learn more, so I don't repeat the
same issue in the future. Has this anything to do with the Ruby or Rails
version?

Warm regards,
Igancio

—
Reply to this email directly or view it on GitHub
#169 (comment).

[iox]

Ok, I think I found what happened:

member_class is a hobo extension that does not return NilClass. It returns nil. (https://www.omniref.com/ruby/gems/hobo/2.0.1/symbols/ActiveRecord::Associations::CollectionProxy/member_class)

In my test system, the existing code is not returning any error. I can see this message correctly:

Can you provide with an example to reproduce the crash?

[stevemadere]

Well at least with some versions of Rails and Hobo
it is returning NilClass rather than nil.

The condition can just be extended to check for both
being nil or equal to NilClass and that would solve
it in both of our environments.

On Mon, Nov 9, 2015 at 5:15 AM, Ignacio Huerta notifications@github.com
wrote:

Ok, I think I found what happened:

member_class is a hobo extension that does not return NilClass. It
returns nil. (
https://www.omniref.com/ruby/gems/hobo/2.0.1/symbols/ActiveRecord::Associations::CollectionProxy/member_class
)

In my test system, the existing code is not returning any error. I can see
this message correctly:

[image: captura de pantalla de 2015-11-09 12 13 22]
https://cloud.githubusercontent.com/assets/452823/11032363/491fe82e-86db-11e5-896a-6c4ed9e75085.png

Can you provide with an example to reproduce the crash?

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Reply to this email directly or view it on GitHub
#169 (comment).

[iox]

Oh, that explains it, there must be some Rails version change issue. Thanks a lot for your patience!